In each of the following questions, choose the option that best completes the gap(s).
Each of the answers ______ correct.
The sentence "Each of the answers ______ correct" tests subject-verb agreement with the indefinite pronoun "each." The word each is always grammatically singular, regardless of the plural noun that follows it in the prepositional phrase "of the answers."
Because "each" is singular, it requires the singular verb is. The correct sentence reads: "Each of the answers is correct."
"Are" and "were" are plural verb forms that would agree with "answers" but not with "each," which is the true subject. "Have been" is also plural. A common mistake is to let the plural noun nearest to the verb ("answers") influence the verb choice, but the grammatical subject is "each," and it governs the verb.
Other singular indefinite pronouns that follow the same rule include: every, everyone, everybody, everything, either, neither, nobody, no one, someone, anybody.